Like Tevez, Vidic is understood to feel undervalued and he has attracted the interest of several leading clubs, including Real Madrid and AC Milan. The 28-year-old Serbia international's contract expires in 2012 and United are yet to talk about extending it.

City's interest is unlikely to be welcomed by Sir Alex Ferguson, United's manager. He has had to deal with problems in central defence all season, with both Vidic and Rio Ferdinand frequent absentees.